Resistance unit



Jan. 1, 1946. E. W. DAvls RESISTANCE UNITS Filed Aug. 15, 1942 Patented Jan. 1, 1946 UNITED s.'1.1iTr1a:s PATENT E;

zggsaosrr RESISTANCEZUNIT; f

. Ernest W. Davis,r River Forest, 1lh,. assgnor to.`

StewartfWarner Corporation-,W Chicagp. Ill`;, ai corporation of Virginia;v Applicationugustf, 1942,; S.er,ial:Nlij454,Z3

8 Claims. (Cl. 137.-152).

My; invention relates to.y resistance unitsA and; more`r particularly to resistance. units; of' the. kinds; used in centralized lubricating systems.

In; centralized lubricating systems, lubricant; from a. central sources such. asa lubricantV com-.- pressorisiorcedjunderpressurethrough afbrancl'ry piping system to a plurality of bearings requiring-f lubrication. Metering means in the form. of measuring valves or resistanceunits are commonly provided inthe Various' branches of the. pipingn systemV in order properly `to l distribute and apportion thev lubricant among the-several bear-- ingsa The bearings supplied with lubricant bymeans of 'such a centralized' lubricating vsystem common-- l`yoffer derent'resistances vto thef-infloW-of lubricant and' numerous' attempts have been-made to provide inexpensive and reliable -lcentralizedllubricating systems'which will properly apportionthe lubricant among the several bearings regardless of` their differences in resistance to 1 the'Y inflow' of lubricant.

An object of' myV invention istoprovidea resistanceh unit which shall' automatically compensate forA differences in-resistance' oieredbyj the' bearing' towhich iti'sattached? and Whiclr Y Y a centralizedA lubricating system in accordance with their. needs.

Another object of. my inventionis toplovide; resistanceY units which automatically-adjustmenseI've's-to compensatefor variations'in resistance ofthe several' bearingsof' a` centralized lubricating system and; which canbe. installed` by men; M10, haven no special' training. in the design con.- struction.,v or` operationof4 centralzedlubricating; systems.

Another object of my invention is to providea. resistance; unitwhich issuitable fon use .with bearings having. a. wide. diierlencev in resistanceto. inflow. of lubricant.r

a a: fulcrum 38- illustrated-ass constituting-A ani'ntee Anotnerzabject; ot mrfivnventicrr. ist-9 prcvide.: at resistance hav-ing. al. minimum.- of partsf-V andi sor. constructed; thats itl is not easily.Y aiected.

enormer: impnritiem contained; in ther lubri:N cant;

VQtner objectszandcadyantaeess willbecnmef-aue parentV as. descriptiompmceeds..

In'v theA drawingl` Eig..1.is;a;.sectionatviewfo ampreierredembmie ment. ofmy.;y inventions; anti Fig; 2 is; a. sectionahview as.. secondil embodiment; or my:l inventom...

In Fig..1-,.1hare ai.measuring.;vali/'e3` comprising a. body: I2. off metal?. or: otherf materiali andz providing a: nipple M.. threaded; for: engagement; with thethreaded. hole; lzlfl: my.. the: bearing member:i I8. Thealiolea Hi andnir'iple l': are'y preferablyf tapered: in accordanceV with .consvenc'ionalpractice sor that the.;y nipple Hl' formsf. a' lubricantztype-seal-with the bearing-1 IB Whernfirm 1y screwed thereinto'..

rIlhe` body` l-T provides:azborev 202 im communica-.z tion= with af passage 22. through. the;A nippl'ei Mi.. The bore- ZIT: is providediwith a smoothacylindrr-f calV internat walll formingt a. suitable surface for' enacting-'- with a plug zdf-having; a, helcal groavei Ztl which forms a= long passageoffrelativeyflargef cross-section andi' relatively higharesi'stancelfttlies flowoigreasee or) similar" lubricant therethrough.

Theresistancen plug 2 is: a?. snug t in the 20, but; isreadilyg sl'idabl'etherein; The;upperfendA of thef plugr 2k isprovided' with af.. U lsliapecf 2-8 whiclrv isJ adapted to receive-the' arm- 30 ofia.- lever 32. This lever is bentf-as` indlcatedi'at uit@ provide a= recessf 361whicli restsuponthe apexof gral'- partof the bodya |21'. The-apex of-thes-ful crunr 3u constitutes a.: lin-ire` edge` which' supports? the lever 32j but oersfaa minimum` off resistance,` topivotal movement' oithisleveirabout' this apex..

TheupperendL-o thevbody' I 2hasa lateral extension; 40 which includes the` fulcrum- 3.8" and*- a; spaceJQiforthe amid-4? oftle-lever cap'f' 415i is attaclrxedt to: tliezupperendi of the` body I'2 b3( screws; bolts.; or anyotber:suitable-attaching means, and;.hasa threadedoperng 4% adapted*to receiveV the' reducedi endly 50 off, ai pipe't tt-ingj 52; The tt'ing 52 hasI a: recess 54j for; receiving one* eridL of a'pipeSE' which constitutes one branchk @Q ofacentralizecrlubricating;system. Tubul'arrruti 5K and; cpnipres siori ring; 601 cooperate with the fitting, 5 2; to proyide'; a. compression coupling u. with the; pille.; 56j and this.` borel terminatesratt'itsf lower end in a recess 64 which constitutes a. valve seat for a ball valve 66. In the position of the parts shown in Fig. 1, lever 32 is holding ball 66 in contact with seat 64 and the resistance plug 24 is suspended from the one end of the lever 32.

In the operation of that embodiment of my invention shown in Fig. 1, the lubricant under pressure is suppliedgthrough pipe 56 and flows downwardly in bore 62. This lubricant displaces the ball valve 65 by pushing it downwardly away from seat 64 thereby providing an opening through which the lubricant can iiow into the spaceY 42. As the ball valve 66 is moved downwardly, lever arm 32 therebeneath is also moved downwardly and lever 32 is pivoted in a counterclockwise direction about the fulcrum 38. This pivotal moveunit and that the operative parts of each resistance unit automatically adjust themselves to poment of the lever 32 raises the resistance plug bearing offersl relatively little .resistance to the inflow of lubricant, the lubricant ows rapidly throughthe helical passage 26 which offers a high resistance to this rapid flow Yof lubricant. YThis high resistance builds -up lubricant pressure in the chamber 68 above the plug 24 and this -lubricant pressure acts uponthe uppen end of this plu'g and moves it downwardly in the bore 20.

This downward movement of the plug 24 pulls r; j

the righthand arm 30 of lever 32 .downwardly and causes this lever to pivot in aclockwise direction about its fulcrum 38. Lever arm 44 is moved upwardly by this clockwise movement of the lever 32 and ball valve 66 is moved toward its seat 64.

As ball valve 66 approaches its seat 64, inflow of lubricant to chamber `42 isrestricted and the lubricant pressure in this chamberl and in chamberA 68 decreases. This reduces the pressure available to force lubricant through helical passage 26 and thus reduces the lubricant iiow through thisl passage and tothe bearing. The lever, 32, resistance plug 24, and ball valve 66 finally come to rest in such positions that the ball valve 66 oiersappreciable resistance to flow of lubricant into chamber 42 anduonly part of the lubricant pressure in the pipe 56 is availableto force lubricant through helical passage 26 and togthe bearing surfaces. A

If the bearing, on the other hand,V offers a high` resistance to in flowof lubricant; the lubricant iiows relatively slowly through the passage 26 and the pressure dropracross this helical passageis less. The downward pull exerted by the plug 24 on. the righthand arm 32 of lever 30 is therefore less,l and this lever urges ball valve 66 towardits seat 64 with less force. The ball valve 66 .therefore offers less resistance to iiow of lubricant'dfrom pipe 56 into chambers 42 and 6.8 and sitions which correspond to the degree of resistance oieredby their particular bearing. The

'operative parts of the several resistance units will ordinarily adjust themselves to different resistances since the bearings usually offer different degrees of resistance to iniiow of lubricant. The net result will be that each bearing of the centralized lubricating system will receive its proper proportion of the .entire quantity of lubricant supplied to the system and this desirable condi'- tion will obtain regardless of variations in the resistancesof the individual bearings since these variations v in resistances will be automatically compensated `by the resistance units attached tov centralized lubricating systems to provide different branches with resistance plugs of different lengths so that the bearings supplied with lubricant by some branches will receive less lubricant than the bearings supplied through other branches. In this manner, the lubricating system is adapted to supply various bearings having widely diierent lubricating requirements.

My invention is readily adapted to utilize this common practice and the resistance plugs 24 of y; the different resistance Aunits in a given centralized lubricating system may be of diierent lengths and therefore different resistances. The operation of my novel resistance unit is the same for all lengths of resistance plugs and in a centralized lubricating system utilizing my new and improved resistance units with different `length resistance plugs, the'variations` in individual re,

sistance of -the different bearings will -be automatically compensatedv and the bearings ls up-A plied with quantities of lubricant lproportioned to their individual needs. These proportions will remain constant throughout the-life of the lubricating system and such variations in resistance.

of individual bearings as mayeoccurfrom time to time-will be automatically compensated for.

My new and improved resistance unit is formed of a relatively few simple. parts ,.andthese' parts are so designed that they-,can readily be made by conventional machinery and by mass producl tion methods since the tolerances required are alar'gerproportion of the lubricant pressure. in-

the'pipe-56 is available in chamber 68 to force lubricant through the helical passage 26 and into beapparent that mynovel re'sistanceunit auto.

matically vadjusts itself'to' accommodate this well within the rangeV normally encountered in mass production.

` The resistance unitA which I have illustratedr and described is particularly. adapted Vfor use in conduit between the bearing and the resistance unit..

In Fig;""2, I havejillustrateda second forni'llof.' my invention. In this form ,Q f, my'invention.; the resistance unit has a tubular'body '|00 ter-- mi'na'ting at one end in a tapered .nipple L`I'll24 adapted to be threadedly `attached to va bearing |04. The body has a smooth cylindrical bore |06-communicating at its lower fend with a smaller bore |08 formed in nipple|02 and leading tothe bearing surfaces.v The. upper end of the body |00 is closed by a screw cap H0 which may be readily removed for inspection or for any other desiredpurpose.

The body |00 is provided with a laterally projecting boss H2 and a threaded opening ||4 extends through the Vboss ||2 and adjacent part ofthe body 100. A fitting ||6 has a threaded nipple ||8 screwed into the opening 4. This tting H6 has a recess '|20 for receiving one end of a branch pipe |22 which is secured to the ftting IIB by tubular nut |24 and compression ring |25.

The fitting H has'a bore |28 which forms a communication between the pipe |22 and the bore |06 of the body |00. The bore |28 terminates in a aring portion |3|which constitutes a seat for ball valve |32.

. A .resistance plug |34 is located in that part of the bore `|05 which is between inlet bore ||8 andl outlet bore |08. The plug |34 is slidable in the bore |06 and has a helical groove |36 constituting a resistance passage whereby the lubricant may pass to the .bearing surfaces. The plug |34 is illustrated as being somewhat shorter than the plug 24 of the embodiment of Fig.A 1, but it willv be understood by those skilled in the art' that these plugs canbe made of different lengths tofafford different degrees of resistance to the flow of lubricant therepast'.

Ahead |38 is made integral with or rigidly at-y tached to the resistance plug |34 and a `reduced portion or neck |40 is located between the head |38 and plug |34. The annular space |42between the neck |40 and body |00 isv connected by bores |44 and |46 with the space |48 between the head |38V and screw cap H0. The. head |38: is provided with a tapered surface |50 whi'cha coacts with ball valve |32 to move this valve toward its seat when plug |34 and head |38 move downwardly.

When lubricant is supplied through pipe |22 to the resistance unit of Fig. 2, this lubricant moves ball valve |32 away from its seat and this movement of the ball valve pushes head |38 and resistance plug |34 upwardly as shown in Fig. 2. Lubricant then flows into annular space |42 and through helical passage |36 and bore |08 to the bearing surfaces. The resistance which passage |36 olers to the flow of lubricant therepast creates a diiierential pressure between opposite ends of this passage and this diierential pressure urges plug |34 and head 38 downwardly and tends to seat ball valve |32.

When the bearing |04 offers little resistance to inflow of lubricant, there initially occurs a relatively large flow through the helical passage |36 thereby creating a relatively large diierential pressure between opposite ends of this passage. This large diierential pressure urges ball valve |32 towards its seat |30 and restricts flow of lubricant into annular space |42. This cuts down the fluid pressure in the space |42, thereby reducing the flow through helical passage |33 and into bearing |04. If, on the other hand, the bearing |04 oiers high resistance to inflow of lubricant, a relatively small flow of lubricant occurs through the passage |36 and the differential pressure between opposite ends of this passage is relatively small. Ball valve |32 is thereby urged toward its.' seat l30by only a 'smallforce and most of the fluid pressure .in the pipe: |22 is available in annular space |42'to force lubricant through passage and to .the bearing.

.From Vthe foregoing description of Figs. 1 and 2,1 it will be apparent that the operations ioflthese. two 'embodiments of my invention are essentially; the same and that both of -these embodiments: automatically compensate vfor differences in vthez resistances of the bearings themselves. f It is usual, in centralized lubricating systems to .providex screens or other filters or strainers for removing: impurities from the lubricant, and such vscreens are commonly provided either at the lubricantv compressor oriat the resistance units or in both,v places. While I have not illustrated my resist'- ance units as being provided with strainers, any conventional or desired means for removing im purities from the lubricantmay be used in. connection'. with these resistance units. 'In this con--` nection, I wish to point out that the design of4 these units is such that they are not easily clogged or interfered with by the presencev of impuri-y ties in the lubricant.

My invention is susceptibleto numerous vari.. ations and modifications in addition to those-i1- lustrated and described. My invention is, therefore, not to be construed as limitedzto the details4 shown and described, but is to be eonsideredasincluding all variations and :modifications falling within the scope of the appended claims.

Iclaim: 1 1. A resistance unit comprising a body having a bore'therein, a plug slidable in. said bore and having a passage of xed dimensions offering 1re.-- s'istance .tothe flow of lubricant therethrough, an inlet through which lubricant is supplied 'to `said bore, a valve for restricting flow of lubricant through said inlet, said valve being urged toopen position by lubricantV pressureV at said-inlet, and means responsive to the differential pressure across said plug to urge said valve toward closed position. l

2. In aresi'stance unit of the class described;v 45 the combination of .a bodyflhavingacylindrical bore therein, a plug closely fitting said bore and slidable therein and having a' helical groove of fixed dimensions cooperating therewith to form a high resistance lubricant passage, said plug being moved in said bore in response to pressure diilerentials between the opposite ends of said plug,

a lubricant inlet for said bore, a ball valve for regulating ow of lubricant through said inlet,

said valve being urged toward open position by lubricant pressure at said inlet, and means for shifting the position of said valve to correspond to different positions of said plug in said bore resulting from differences in the differential pressure across said plug.

3. In a resistance unit of ,the class described, the combination of a body having a cylindrical bore therein and a nipple provided with an outlet communicating with said bore, a plug slidable in said bore and having a passage offering xed resistance to the ow of lubricant therethrough,

said plug being moved in said bore in response to pressure diierentials between the opposite ends thereof, a pipe for supplying lubricant pressure to said bore, a valve controlling flow of lubricant from said pipe to said bore and urged toward open position by lubricant pressure in said pipe, a pivoted lever having a part engaging said valve, and means connecting said lever with said plug so that movement of said plug resulting from increases in the differential pressure across said plug creates movement of said lever and of said valve toward closed position.

4. In a resistance unit of the class described, the combination of a body having a bore therein. and adapted to be connected to a bearing requiring lubrication, a member slidable in said "bore and oiering xed resistance to flow of lubricant therethrough, said member Vbeing moved in said bore in response to pressure diierentialsbetween the opposite ends thereof, an inlet pipe for supplying said bore with lubricant under pressure, a ball valve for controlling flow of lubricant from said pipe into said bore and urged toward open position by lubricant pressure in said inlet pipe, a lever having one arm engaging said valve, a U- shaped strap carried by said member and engaging a second arm of said lever, and a fulcrum for said lever interposed between said valve and strap the arrangement being such that increases inthe diiTerential in pressure across the plug effect movement of said valve toward closed position.

5. A resistance unit of the class described, comprising in combination, a tubular body having'a nipple at one end, said body having a relatively large cylindrical bore and a smaller outlet, bore extending through said nipple, a plug slidable in said larger bore and having a. passage offering xed resistance to flow of lubricant therethrough,

a tapered head in said larger bore, a neck con.

necting said head and plug, an inlet for said larger bore through which lubricant under pressure may be supplied, and a ball valve for controlling ilow through said inlet, said valve being located between said plug and head, said valve being urged to closed position by said head on increase in diierential pressure acting across said plug and to open position by lubricant pressure in said inlet.

6. A resistance unit of the class described, comprising a tubular body providing a bore, means forming an outlet at one end of said bore, a closure for the other end of said bore, a resistance plug slidable in said bore and offering fixed resistance to flow of lubricant to said outlet, an inlet for supplying lubricant under pressure to said bore, a head slldable with said plug. a valve member between said plug and head the arrange.. ment being such that the valve is urged by the latter to close said inlet when the pressure diierential across said plug increases, said member being urged to open position by lubricant pressure in said inlet.

7. In a resistance unit of the class described, the combination of a body having a. bore therein, a resistance .plug slidable in said bore, and providing a restricted passage of fixed dimensions for ilow of lubricant therepast, an inlet for said bore, means for restricting lubricant iiow through said inlet, said means being urged toward nonrestricting position by lubricant pressure at said inlet, and means operatively connecting said plug with said flow restricting means to urge said ilow restricting means toward now restricting position by an increase in the differential in pressure across said plug, whereby said ilow restricting means is responsive to the pressure diierential between opposite ends of said plug.

8. In a resistance unit of the class described, the combination of a body having a bore therein, a member slldable in said bore and having a passage oifering xed resistance to ilow of lubricant therethrough, an inlet passageway at one end of said bore adapted to be connected to a source of lubricant under pressure, outlet means at the other end of said bore adapted to be connected to a bearing requiring lubricant, said member having opposite ends exposed to the pressures existing at opposite ends of said passage, and an unbalanced valve for varying the lubricant pressure in the inlet end of said bore with variations in pressure drop between the ends of said passage, said valve having a part exposed to lubricant pressure in said inlet passageway and being urged thereby toward open position, said valve being connected to said slidable member whereby increases in the differential pressure across said member act to move the valve toward closed position.

ERNEST W. DAVIS. 

